Tool



jam. 29, 1929.

W. BARTELS TOOL Filed Dec. 11, 1926 2 Sheets-Sheet 1 N m P 4 J 2U IIIL 0 LI 9 5 2 INVENTOR A TTORNE Y W. BARTELS Jan. 29, 1929.

TOOL

Filed Dec. 11. 1926 2 Sheets-Sheet 2 7 Exsiill ATTORNEY v Patented Jan. 29, 1929.

UNITED STATES WILLIAM BARTELS, OF NEW YORK, N. Y.

TOOL.

Application filed December 11, 1926. Serial No. 154,204.

My invention relates to tools and more particularly tools to which a rotary motion is applied, such, for instance, as reamers, drills, and the like. The object of the present invention is to produce a tool provided with an adjustable cutting member, which during the operation of the tool is gradually moved to a slanted or wedge-shaped position in such a way that it will produce a conical hole, i. e. a hole wider at the bottom than at the top. A tool of this character is principally designed torv wood-work, to produce conically enlarged holes for receiving dowel-pins, but, of course, the tool can be likewise used on any other material and, therefore, is not limited to opera-- tions on woodwork.

For a more complete explanation of my invention, I refer to the annexed drawings, on which I have, for purposes of illustration, shown several embodiments of the tool and on which Fig. 1 is an elevational view of one embodiment of the tool showing the cutting member of the tool in the position when not in use; Fig. 2 is a similar view as Fig. 1, showing the. cutting member moved to the full slanted or wedge-shaped position; Fig. 3 is a side-elevation of the tool as shown in Fig. 1; Fig. 4 is a view at right angles to that shown in Fig. 1, partly in section, along line 4-4 in Fig. 1; Fig. 5 is a cross-section along line 55 in Fig. 1; Fig. 6 is a lower end-view; Fig. 7 is a detail viewof the cutting member; Fig. 8 is a detail view of the wedge-shaped slide; Fig. 9 shows a block of wood with holes conically enlarged by the tool, one hole being shown broken away; Fig. 10 is a similar view as Fig. 1 showing a modification, the cutting-member occupying the position when the tool is not in use; Fig. 11 is a view of the same tool at right angles to Fig. 10, partly in section, along line 11-11 in Fig. 10. Fig. 12 is a cross-section along line 1212 in Fig. 10; Fig. 13 is a lower end view and Fig. 14 a detail view of the wedge-shaped slide.

The tool as shown in Figs. 1-8, comprises a shaft 1 adapted to be clamped in a brace or, when shaped as shown in Fig. 2 adapted to be placed in the chuck of a power-driven machine, and the head 2 of cylindrical shape, preferably made of hardened steel. 3 is the cutting member having a longitudinal, preterably cylindrically curved, cutting edge 4 and having secured thereto or, if desired formed integral therewith, a guide-block 5 having a cylindrical surface to correspond is provided with a narrow recess to accommodate a. tension spring 9, which withits one end is secured to the cutting-member, as, for instance, by a screw 10.

Below the said narrow recessed portion, the cutting-member is provided with a larger recessed portion 11 extending all the way down to the end of the cutting member, where the edge formed by said recessed portion 11 is slightly chamtered or bevelled as shown at 12 in Fig. 7. i

13 is a slide (shown in detail in Fig. 8), which is movably set into the lower end of the cylindrically-shaped head 2, which in that portion is provided with a groove to receive the straight portion of slide 13, which, as clearly shown in Fig. 8, is providedwith a wedge-shaped edge 14. To said slide 13 is secured, or formed integral therewith, a cylindrical guide member 15, which is received in a corresponding bore 16 (Fig. 4) provided in the head2. A coiled spring 17is located in said bore adapted to be compressed therein as shown in Fig. 2. The slide 13 is provided with a center pin 18. 19 designates a small plate adapted to be screwed to, or otherwise detachably secured to the slide so as to increase the wedge-shape thereof, if desired. Through the lower end of head 2 extends a pin 20, to act as a stop for the slide.

The operation of this tool is as follows:

With the parts in the position as shown in Fig. 1, the tool is placed into a previously drilled cylindrical hole, and as pressure is exerted on the tool while it is being rotated in the hole, this pressure is transmitted to the center-pin 15 of slide 13, which thereby is gradually moved inwards relative to the cutting member 3, during which movement its wedge-shaped edge moves the cylindrical cutting edge 4 of the cutting member 3 gradually outwards, into the slanted position shown in Fig. 2, when further inward movement of slide 13 is prevented, the spring 17 then having been fully compressed. The reviously drilled cylindrical hole has now t e appearance shown in Fig. 9, that is to say, the bottom of the hole has been conically enlarged so that, when, for instance, a dowel-pin is driven into said hole, there is room for lateral expansion, so that thereafter the dowelpin will be firmly held in the hole.

As the cutting member is ground hollow, it will be evident, that this will allow the wood cuttings to pass out of the hole so that there will be no clogging of the same which would interfere with the cutting operation.

The tool shown in Figs. 10 to 14 also comprises a shaft 21 and a head 22 having a cylindrical surface and a recess to receive therein a cutting-member 23 provided with the longitudinal cutting edge 24, having a cylindrical curve to correspond to the cylindrical surface of head 22. 25 is the slide having the wedge-shaped edge 26 adapted to engage a corresponding edge 27of the cutting member 23 as clearly shown in Fig. 10. The slide 25 also in this embodiment is provided with a round guide-member 28 adapted to move in a corresponding bore 29 in the head 22, in which bore is located a coiled spring 30 which bears against the guide-member 28 and upon the inward movement of the slide 25 is compressed. A screw 31 screwed into the lower end of the head 22 acts as a stop to prevent slide 25 from becoming disengaged from the head. 32 is a center-pin formed at the end of the slide.

The operation of this modification will be readily understood from the foregoing description.

As the head 22 of the tool is set into a pre viously drilled cylindrical hole and pressure is exerted on the center-pin 32 of slide 25, while the tool is being rotated, the slide, being forced inwards relative to the cuttingmember 23 will force the cutting edge of the same, because of the contacting wedge-shaped edges 26 and 27, provided respectively on the slide and the cutting-member, to a slanting position, so that the hole will be conically enlarged as shown in Fig. 9. -When the pres sure is released, the slide 25 will be automatically returned to its original position in Fig. 10 by the expansion of the compressed coiled spring 30, and the tool will be ready for the next cutting operation.

In both embodiments of the invention, the head 2 and 22 respectively is detachably connected to the shaft by means of a screw 33, or the like.

While I have shown and described two embodiments of my invention, I do not of course limit myself to these constructions, as my invention is capable of many other modifications falling within the scope of my invention.

I claim:

1. In a tool, the combination of a shaft, a cylindrical head detachably carried by said shaft and having a recess, a cutting-member adapted to be received in said recess and having a cylindrically curved longitudinal cutting edge to conform to the cylindrical shape of said head, means adjustably pivotally attaching said cutting-member to said head, and a wedge-shaped slide engaging a correspondingly shaped edge on said cutting-member so as to move the cutting edge of the same outwards to a slanting position upon inward movement of said slide relative to said outting-member, and means for automatically returning said slide to its original position upon reverse movement of said slide relative to said cutting member.

2. The combination as specified in claim 1, in which said head is provided with a groove for guiding said slide and a bore to receive a guide-member carried by said slide.

3. In the combination as specified in claim 1, a guide-block provided on said cutting member for preventing lateral displacement of said cutting member during the insertion of the tool.

4. In a tool, the combination of a shaft,

a cylindrical head detachably carried by said shaft and having a recess, a hollow ground cutting member adapted to be received within said recess and having a curved cutting edge to conform to the cylindrical shape of said head, means for adjustably pivotally attaching said cutting member to said head, a wedgeshaped slide engaging a correspondingly shaped edge on said cutting member to move the cutting edge of said cutting membcr outwards to a slanted position upon an inward movement of said slide relative to said cutting member, a center-pin on said slide, and means automatically tending to returning said slide to its original position.

In testimony whereof I aflix my signature.

WILLIAM BARTELS. 

